It's official: the US federal government was shut down for the first time in 17 years at midnight eastern standard time.

Around 800,000 federal workers now have no job to go to, and the Statue of Liberty, Grand Canyon and Smithsonian Institution will close their doors to the public.

The White House budget director ordered US federal agencies to begin closing down after Congress failed to pass a budget to avert a government shutdown.

"Agencies should now execute plans for an orderly shutdown due to the absence of appropriations," said Sylvia Mathews Burwell, director of the White House Office of Management and Budget said in a memo on Monday night.

The order was issued 10 minutes before the US government officially ran out of money after a day of angry brinkmanship between the Republican-controlled House of Representatives and the Senate, where Democrats have the majority.

Scroll down to read the order in full

Burwell said the Obama administration urged Congress to move quickly so critical government services could be restored. She said the shutdown will affect hundreds of thousands of workers who will be sent home and it will inconvenience millions who rely on federal services.

She said some critical functions, like the military and air traffic control, will remain open.

"We urge Congress to act quickly to pass a Continuing Resolution to provide a short-term bridge that ensures sufficient time to pass a budget for the remainder of the fiscal year, and to restore the operation of critical public services and programs that will be impacted by a lapse in appropriations."

The US embassy in Wellington and the Consulate General in Auckland will remain open tomorrow, despite the federal government shut down.

"Even in the absence of a current fiscal year budget the American Embassy in Wellington and the Consulate General in Auckland are continuing visa services and other operations," a spokesman said this evening.

Americans anxious, irritated as government shuts down

For many employees of the federal government, the shutdown that began Tuesday (Wednesday afternoon, NZT) meant no more paychecks as they were forced onto unpaid furloughs. For those still working, it meant delays in getting paid.

Park Ranger and father-to-be Darquez Smith said he already lives paycheck-to-paycheck while putting himself through college.

"I've got a lot on my plate right now - tuition, my daughter, bills," said Smith, 23, a ranger at Dayton Aviation Heritage National Historical Park in Ohio. "I'm just confused and waiting just like everyone else."

The impact of the shutdown was mixed - immediate and far-reaching for some, annoying but minimal for others.In Colorado, where flooding killed eight people earlier this month, emergency funds to help rebuild homes and businesses continued to flow - but federal worker furloughs were expected to slow it down.

National Guard soldiers rebuilding washed-out roads would apparently be paid on time - along with the rest of the country's active-duty personnel - under a bill passed hours before the shutdown. Existing Social Security and Medicare benefits, veterans' services and mail delivery were also unaffected.

Other agencies were harder hit - nearly 3000 Federal Aviation Administration safety inspectors were furloughed along with most of the National Transportation Safety Board's employees, including accident investigators who respond to air crashes, train collisions, pipeline explosions and other accidents.

Almost all of NASA shut down, except for Mission Control in Houston, and national parks closed along with the Smithsonian museums and the National Zoo. Even the zoo's popular panda cam went dark, shut off for the first time since a cub was born there August 23.

It turns out an institution as massive as the federal government takes some time to grind to a total halt: Many federal workers were being permitted to come in Tuesday to change voicemail messages or fill out time cards. But after that, they were under strict orders to do no work, even check their email.

With no telling how long the budget standoff will last, even programs not immediately affected could run out of cash.Barbara Haxton, executive director of the Ohio Head Start Association, said its preschool learning programs would be in jeopardy if a shutdown lasted more than two weeks. March's automatic budget cuts meant nearly 3000 children lost access to services and there could be dire consequences if the budget standoff drags on.

"It's not as though this is a throwaway service. These are the poorest of the poor children," Haxton said. "And our Congressman still gets his paycheck. His pay doesn't stop and his health insurance doesn't stop."

Obama's message to troops

President Barack Obama has told members of the military he is working to get Congress to re-open the government as soon as possible.

In a video message to troops. Obama said those in uniform would remain on duty as usual.

He said he had signed a law ensuring troops get paid on time.

Operations in Afghanistan and elsewhere would continue and the US would ensure those in harm's way had what they needed, he said, but Defence Department civilians may be furloughed.

Obama told the troops that compounds the damage from spending cuts that have already affected the military.

Hundreds of thousands of government workers will be off the job, but some essential services will continue.

The Democrat-led Senate voted to kill two House-passed amendments that chipped away at Obamacare, which the House had passed less than an hour before.

Democrat House Majority Leader Harry Reid said Republicans were insane for repeatedly targeting Obamacare in a government funding bill.

"Albert Einstein said when defining insanity as follows, quote, 'Doing the same thing over and over again and thinking you're going to get a different result,'" Reid said.

'Republicans insane'

"Einstein was a genius, but it doesn't take a genius to figure out that the proof is watching the House Republicans, because they've lost their minds."

Due to a lapse in government funding, this account will not be active until further notice.

Obama appeared resigned to a shutdown earlier in the day, stepping into the White House press room to reiterate that the shutdown would be the fault of the "extreme right wing" of the Republican Party, referring to the conservative Tea Party.

He also reassured the public that while poor people and seniors, among others, would continue to receive benefit checks in the event of a shutdown, many other functions of government would grind to a halt, throwing "a wrench into the gears of our economy."

And he taunted Republicans about Obamacare, a program aimed at providing healthcare coverage to millions of uninsured Americans. It "takes effect tomorrow no matter no matter what Congress decides to do today ... you can't shut it down."

Republicans say the launch on Tuesday of new online government health insurance exchanges will cause premiums to rise and deter companies from hiring new workers.

The White House later said Obama placed calls to top lawmakers, continuing to press the Republican leadership for six weeks of government funding, free of any "ideological riders."

Americans are split over whether funding for Obama's signature healthcare law should be linked to measures that pay for US government operations, but more will blame Republicans if the government has to shut down on Tuesday, according to a new Reuters/Ipsos poll.

The standoff does not bode well for the next political battle, a far-more consequential bill to raise the federal government's borrowing authority. Failure to raise the $16.7 trillion debt ceiling by mid-October would force the United States to default on some payment obligations - an event that could cripple its economy and send shockwaves around the globe.